If you can find a small church that is growing, and they need more space, then I would lease it to them with an option to purchase.

I would like to know What others think are the most important items to be checking when doing the initial walkthrough?

Many people lease for the summer months (July-Sept) at 4-5X normal rents (up to $10k during sailing events, tennis tournaments etc.), then cut the rate for off season months to Salve Regina students, or Navy on extended TDY /training.

It is a checklist item, not something to strategize around.

I’ve locked up a lease option on a small commercial property and the house behInd it, that’s been vacant for five years.

Your list is pretty comprehensive, I would check deeds, title, leases, management agreement, vendors, etc.I tend to disagree with the bolded portion though.

I think on your next one I would look around for a few items that would look like higher finishes.And while you are in a tough area of town, I am somewhat surprised you aren't able to sell it. 

Save up reserves knowing you will need to update some big ticket items and just replace as things break. 

I have done some flips and lease options along with a few rentals.

I'm in the process of breaking my lease and moving into a recently purchased SF home.